Rated 5 out of 5 stars
Wow, have I missed this! :)
Managed to get it going again so thanks to lengoldstein for pointing out the excellent Disable Add-on Compatibility Checks https://addons.mozilla.org/en-US/firefox/addon/checkcompatibility/
Also brings the must have Classic Compact Options https://addons.mozilla.org/en-US/firefox/addon/classic-compact-options/
Even tighter spacing! :D
5/5 for CC of course!